President Donald Trump will be giving his formal political rival, Ted Cruz a campaign boost.

The president announced Friday that he will host a “major” rally in support of the Texas Republican. The move is aimed at solidifying Cruz’s support for reelection as polls against his Democratic opponent, Rep. Beto O’Rourke tighten.

“I will be doing a major rally for Senator Ted Cruz in October. I’m picking the biggest stadium in Texas we can find,” Mr. Trump tweeted. “As you know, Ted has my complete and total Endorsement. His opponent is a disaster for Texas — weak on Second Amendment, Crime, Borders, Military, and Vets!”

The two took jabs at each other during the 2016 GOP primaries. Cruz was often mocked by the billionaire as “Lyin’ Ted” among other insults on the campaign trail. Cruz, in turn called Mr. Trump a “sniveling coward.”

“The polls are too close,” the senator tweeted Friday with an image showing him leading by a single percentage point. “Your support can help change the direction of this race.”

O’Rourke’s massive fundraising and support from Hollywood superstars like Rosie O’Donnell and Alyssa Milano has Democrats optimistic – even if Texas is viewed as a longshot.

O’Rourke and Cruz have both raised nearly more than $23 million. As of the end of the second fundraising quarter on June 30, O’Rourke had $14 million on hand compared to Cruz’s $9 million according to Federal Election Commission documents.